@ElsonThomas For me it works. It will take a few secs ... til 10 or 15 secs. Enable IGMP. And TP-Link sent to me another firmware upgrade.

Problem solved on my side. See my last comment.

My DECO's are back 2normal now after TP-Link new firmware and enabling the ICMP Feature.

@JuraUrban @TP-Link Could you please figure it out? Are you looking professional or not? You did such a good work, but now everything is broken. I;m not able to use the system anymore. I want to...

I intend to return as well my devices, two M4R and two E4R. All of them are with the latest firmware but the clients still doesnt appear in the device list. So frustrating.